Where is array's length property defined?

Question

We can determine the length of an ArrayList using its public method size(), like

ArrayList arr = new ArrayL         


        

Answer 1

It's defined in the Java language specification:

The members of an array type are all of the following:

• The public final field length, which contains the number of components of the array. length may be positive or zero.

Since there is a limitless number of array types (for every class there is a corresponding array type, and then there are multidimensional arrays), they cannot be implemented in a class file; the JVM has to do it on the fly.